Cellulosic products



July 27, 1965 H. N. NELSON CELLULOSIC PRODUCTS I 3 Sheets-Sheet 1 Filed July 31, 1962 July 27, 1965 H. N. NELSON 3,197,109

CELLULOS I 0 PRODUCT S Filed July 31, 1962 3 Sheets-Sheet 2 July 27, 1965 H. N. NELSON 3,197,109

CELLULOS I 0 PRODUCT S Filed July 31, 1962 3 Sheets-Sheet s W l l l k 1 I I l8-' l I I l 32u I --|5 12 ,300 Q i 20-- g l I FIG.9.

United States Patent 3,197,169 CELLULOSIC PRGDUCTS Howard N. Nelson, Neenalr, Wis, assignor to Kimberly- (Ilarlr orporation, Neenah, Wis, a corporation of Delaware Filed July 31, 1962, Ser. No. 214,462 8 Claims. (Cl. 22937) This invention relates to improvements in shipping containers and the like, with particular references to boxboard cartons.

A primary object of the invention is to provide improvements in carton end flap closures.

Another object is to provide an improved adhesive seal on cartons of the type commonly employed in the packaging of light weight articles in relatively large cartons of light weight fiberboard stock.

Another object is to improve the end flap construction of cartons of the full economy type commonly shipped knocked down, thereby insuring, upon assembly, a more effective adhesive seal, hence a stronger carton.

Another object is to provide improvements in the hinging of carton end flaps in a manner to improve subsequent gluing and assembling operations.

A further object is to provide a carton securely sealed against the entrance of foreign elements such as dust, dirt and small animal life. a

Other objects and advantages will become apparent to persons skilled in the art, upon examination of the drawings and description, without departure from the concepts herein taught or defined in the appended claims.

In the drawings, in which like parts are identified by corresponding reference numerals,

FIG. 1 shows in perspective a carton incorporating the inventive principles herein taught.

FIGS. 2 and 3 are vertical longitudinal sections of the carton of FIG. 1 extending through one of a pair, of inner end flaps and both of a pair of outer end flaps forming a sealed closure at one end of the carton.

FIG. 4 illustrates in enlarged detail the structure of FIG. 2.

FIG. 5 is a fragmentary perspective View illustrating deficiencies of prior art structures which the present invention eliminates.

FIGS. 6 and 7 are fragmentary perspective views of alternate hinge line constructions. I

FIG. 8 is a plan view of a carton blank showing the hinge line configurationfor the inner flaps in one embodiment of the invention.

FIG. 9 is a fragmentary view of a carton blank showing another variation of the inner flap hinge line.

FIG. 1 illustrates the inventive concepts as incorporated in a generally rectangular carton, generically designated 10, an end closure thereof being shown partially open prior to final closure and gluing. A pair of inner flaps, generically designated 12, 14 comprise integral extensions of side wall 16 and an opposite side wall, not shown. The inner end flaps are defined by lines of weakening which serves as a hinge line, such as by lines of embossing which insure retention of maximum corner strength. As shown in FIG. 5, a portion of an outermost flap may be difilcult to seal, due to the thickness of the stock, hence may permit access to the carton interior to allow dust or small insects to find entrance to the carton interior. The infolding of outer flap 18 as shown in FIG. 5 (the inner flaps are not shown) positions the side margin thereof against the rigid corners between the side walls and the inner end flaps which provide a rigid marginal backing.

When carton sheet stock is of negligible thickness, as for example kraft paper or the like, a second outer flap 20 may overlap the free margin 22 of flap 13 without a resultant spacing therebetween, as illustrated by channel 24. However with thicker stock, such as boxboard, the sheet stock is ramped in a plane leading from upper corner 26 to the free margin 22 of flap 18, and the interflap spacing 24 results. It is common practice to apply glue only to the inner surface of overlapped flap 20. A thin film of glue thus applied to a very thin flap results in elfective sealing, since as flaps 18, 20 are brought into pressed engagement outer flap 20 will deform sufficiently along margin 22 to close channel 24, and the adhesive bond will prevent its spring back. However in boxboard cartons of the type employing, for example, sheet stock of a 20 mil thickness or greater, resulting channel 24, especially adjacent the free margin 22 of flap 18, may not be completely closed due to stock deformation andthe film of glue applied to the under surface of flap 20. Even though channel 24 maybe closed during the pressurized sealing of flap 20 in partially overlapped relation to flap 18, the non-overlapped, or upper portion thereof as shown in FIG. 5, after being forced into tight sealing engagement with the corresponding area of the underlying inner flap, may spring back with resultant re-opening of channel'24;

Cartons of the type herein illustrated are commonly employed to house articles such as sanitary napkins and medicinal bandages requiring complete protection from the infiltration of dust and insects to the cartoninterior. Many such cartons are of sufficient size to require the employment of sheet stock within the above mentioned thickness range, hence the problem of obtaining aneilective carton end closure while employing a minimum of sheet stock has long. been an industry problem.

Referring to FIGS. 1 and 3, inner flaps 12, 14 are integral extensions of corresponding side Walls 16 formed by hinge lines extending transversely of side Wall 16. Each hinge line consists of general lines of weakening comprising two relatively oifset segments. The'hinge line segments preferably consists of lines of embossing, with one of said segments such as upper segments 28 being at least in part laterally offset as shown at 30 from at least a portion of the remaining segment 32. It is preferable that one of the hinge line segments 28, be disposed obliquely of the other segment 32, or that they both be ob liquely disposed in respect to terminal points of the hinge line, rather than being disposed in parallelism. The seg ments may however be disposed in parallelism if it is not mandatory that corresponding upper and lower corners of the end closure structure be positioned in exact vertical alignment. FIG. 6 illustrates a hinge line consisting of an upper segment 28a extending obliquely outwardly of corner 34a to a position of maximum offset at 30a in respect to a vertical segment 32a. FIG. 7 shows segment 28b oliset in parallelism to lower vertical segment 32b. The FIG. 6 structure permits vertical alignment of carton corners 34a, 36a, whereas the FIG. 7 structure results in a slight vertical ofiset of corresponding corners 34b, 36b.

FIGS. 8 and 9 give a clearer picture of the inventive concept by showing plan views of a typical carton blank having segmented hinge lines for the inner flaps in which the hinge line segments are olfset.

In FIG. 8, inner flap 12 is shown connected to side wall 16 by a hinge line composed of two offset segments 28a and 32a. Segment 28a extends obliquely outward from corner 34a to a point of maximum offset at 30a in respect to segment 32a. Inner flaps 14, 15 and 17 are shown with similar segmented hinge lines where connected to the side walls. When the blank is folded on these segmented hinge lines in setting up the carton, the resulting corners take on the configuration shown in FIG. 6.

- ta 1 FIG. 9 is a fragmentary view showing a modified hinge ine. side panel 16 by a hinge line having offset segments 28b and 32b. This arrangement differs from FIG. 8 in that segment 28b extends from corner 34!) in parallelism with segment 32b, rather than obliquely. The segments are offset at point 30b. vWhen a blank is folded on this type of segmented hinge. line in setting up the carton, the resulting corners take on the configuration shown in FIG. 7. While optimum end sealing is' obtained through the employment of both an offset hinge line separating the paired carton walls from the respective inner flaps; combined with an offset shoulder line 38 extending along each of the inner flaps in registry with the hinge shoulder offset 30, the invention is not necessarily limited to the inclusion of both of those features. Even in the absence of a shoulder 38 extending across or partially across each of the end flaps, portions of each inner flap adjacent the offset portion 30 of the hinge line are forced into planes offset as the result of the inward folding of the inner flaps. It thus is apparent that upon complete inward folding of that outer flap the end margin of which isbrought into registry with the hinge line shoulder 38, at least corner portions of the flap will assume a recessedrelation to adjacent centersurfaces of each inner fiap throughout at least a small area. Upon infolding and sealing the remaining outer fiap to the three flaps thus infolded an effective seal may be obtained in the absence of an objectionable channel-like opening such as shown at 24, FIG. 5. However since reliance must be placed on relatively small portions of the flap. structure to retain the seal against opening, it is preferable that the inner fiap shoulder line 38, as shown at FIG. 1 be combined with the offset hinge line shown therein to insure that the seal is, maintained throughout larger portions of the surfaces of flaps 12 and 18, respectively. a r Other modifications and adaptations of the invention will become apparent to persons skilled in the art without departure from the concept taught herein, the scope of which is defined in the appended claims.

I claim:

1. In a carton fabricated of box-board sheet stock, a pair of end flaps comprising integral extensions of opposite cartonwalls and defined by hinge lines including a pair of linear segments, portions of which are laterally offset one from the other in non-overlapping relation, whereby infolding of said flaps in right angularity to said walls results in the formation of a shouldered hinge line while effecting the positioning of adjacent areas of the flap surface in planes offset one fromthe other.

2. Thecarton of claim 1 including a second pair of end flaps in right angularity to said first pair of flaps extending from a second pair of opposed carton walls and adapted to be overlapped to enclose said first pair of flaps, the underlying flap of said outer pairbeing dimen- In this figure, inner flap 12 is shown connected to V sioned for recessed registry of marginal portions thereof with the shoulder portion of said hinge line.

3. The device of claim 2' wherein the shouldered portion of said hinge line is of a depth substantially equal to the thickness of the carton sheet stock.

4. The carton of claim 2 wherein both pairs of flaps are folded inwardly with one of the 'outer flaps partially overlapping the other and adhesively bonded thereto and to the uppermost planar portions of the two inner flaps.

5. In a carton fabricated of box-board sheet stock, a pair of end flaps each formed as an integral extension of opposite carton walls by a hinge line extending transversely of the wall, said hinge line comprising two portions offset one from the other in non-overlapping relation, and an offset shoulder extending from a positio n of registry with said fold line offset and longitudinally of each flap in parallel spaced relation to the side margins thereof, whereby inward folding of saidflaps in right angularity to their associate walls positions flap portions adjacent said shoulder in offset non-planar relationship.

6. In the carton of claimS, a second pair of end flaps each formed as an integral extension ofthe remaining two carton walls by a straight hinge line extending transversely of said walls, saidsecond pair of flaps being disposed in right angularity to said first pair of end flaps and adapted for inward folding over said'first pair of end flaps, one flap of said second pair being of a size to position the free end marginthereof, when folded inwardly, in registry with the offset shoulders of the inner flaps and with the outer surface thereof in substantially co-planar relationship to the outermost offset surfaces of said first mentioned flaps. 7

7. The carton of claim 6 wherein portions of said first mentioned flaps are offset to an extent generally corresponding to the thickness of the carton sheet stock to provide a recess for the reception of the free end of an outer flap in substantially flush relationship to the remaining portion of said recessed flap. 7

8. In a carton fabricated of box-board sheet stock, a pair of end flaps comprising integral extensions of opposite carton walls and defined by hinge lines extending transversely of each wall and each including linear segments, portions of which are laterally offset one from the other in non-overlapping relation, one of said segments extending obliquely from a maximum position of offset to a wall side margin, whereby said flaps are inwardly pivotable about a common axis disposed normally of said sidewalls.

References Cited by the Examiner UNITED STATES PATENTS 2,324,757 7/43 Botley 229-37 2,713,454 7/55 Nute et al. 229--37 THERON E. CONDON, Primary Examiner.

GEORGE O. RALSTON, Examiner. 

8. IN A CARTON FABRICATED OF BOC-BOARD SHEET STOCK, A PAIR OF END FLAPS COMPRISING INTEGRAL EXTENSIONS OF OPPOSITE CARTON WALLS AND DEFINED BY HINGE LINES EXTENDING TRANSVERSELY OF EACH WALL AND EACH INCLUDING LINEAR SEGMENTS, PORTIONS OF WHICH ARE LATERALLY OFFSET ONE FROM THE OTHER IN NON-OVERLAPPING RELATION, ONE OF SAID SEGMENTS EXTENDING OBLIQUELY FROM A MAXIMUM POSITION OF OFFSET TO A WALL SIDE MARGIN, WHEREBY SAID FLAPS ARE INWARDLY PIVOTABLE ABOUT A COMMON AXIS DISPOSED NORMALLY OF SAID SIDEWALLS. 